Abstract: 【Purpose/significance】Promoting the government public data opening has become an important method to modernize the governance system and governance capacity, and is also a necessary way to better utilize the value of public data as a production factor. 【Method/process】Shanghai public data is selected and Autoregressive Integrated Moving Average (ARIMA) model is utilized to pre⁃ dict the amount of data released after April 22, 2024.【Result/conclusion】Compared the predicted results of the model with the total amount of existing public data, we obtain the ranking of various fields in government public data. The differences between the results and the ranking results obtained from the questionnaire survey reflect the imbalance between the public's understanding and satisfac⁃ tion with various fields and the government's investment in these field. Suggestions have been put forward for public data opening in areas such as demand forecasting analysis, infrastructure construction, policy standard formulation, and data product supply, while pro⁃ viding theoretical and practical basis for government public data opening.【Innovation/limitation】The paper puts forward a model on prediction of government public data opening. The main limitation is that the model selects the last update time of data as the premise of data release time, and does not study the dynamic process of data update.